Internal-combustion engine



Patented Sept. 2, 1924.

UNITED STATES LOUIS ILLMER, F CORTLAND, NEW YORK.

INTERNAL-CQMBUSTION ENGINE.

Application filed November 20, 1920.- Serial No, 425,345.

T 0 all whom it may concern:

Be it known that I, LOUIS ILLMER, a citizen ofthe United States, and resident of Cortland, in the county of Cortland and State of New York, have invented a new and useful Improvement in Internal-Combustion Engines, of which the following is a specification, reference being had to the accompanying two sheets of drawings, forming part thereof.

My invention relates to internal combus tion engines, more particularly to engines of the so-called scavenging type, and has for its object to increase the efliciency of the engine by providing the same with a simple and reliable pumping means which is incorporated in the design of the engine proper and serves to augment the power cylinder capacity of the engine (Whether Oil or gas) by increasing the air content of the working charge held within the confines of the powercylinder, and also serves to thoroughly scavenge the power cylinder as well.

Another object of the invention is to provide the power cylinders of internal combustion engines with individual pumping units which are contained and embodied in the design of the engine proper and are formed and operated primarily from the working parts thereof.

Another object of the invention is to provide the power cylinders of internal combustion engines with air charging and scavenging means whichis self-contained, automatically operated, and is preferably formed between the working mechanisms of twin units having opposed cranks.

Still another object of the invention is to provide a common power cylinder with an air supply which is obtained through the operations of two opposed pumping cylinders communicating with and discharging into said power cylinder; said pumping cylinders being preferably designed to be intercomrnunicative and provided with a common suction valve which serves as the supply inlet therefor.

Other objects and advantages of the invention will thered from the description fol -iwing herein and considered in conner"'.oii with the accompanying drawings ianerein the invention is shown embodied.

The terms employed herein are used in the generic and descriptive sense to designate the elements illustrated, and are therepower cylinders of the engine unit fore not primarily intended as terms of limitationi.

I In order to illustrate my invention it have shown, without being limited thereto, an embodiment thereof in the accompanying drawings, wherein Fig. 1 represents in the main 2. longitudinal, sectional view taken through a vertical twin cylinder two-stroke oil engine of the single acting type supplied with my invention;

Fig. 2 represents a sectional View taken on line 22 on Fig. 1;

Fig. 3 represents a sectional view taken on line 3--3 on Fig. 2;

Fig. 4 represents a sectional View taken on broken line 4-4 on Fig. 1';

Fig. 5 represents a view showing the inlet valve of the device open;

Fig. 6 represents a plan view of the engine shown in Fig. 1; and 4 Fig. 7 represents a sectional view taken on line 7-7 on Fig. 2.

Like reference numerals refer to like parts throughout the several views of the drawings.

For convenience the similar and corresponding parts of the two engine units will be distinguished from each other by the use of the sufiixes a and b.

The numerals 10 and 10 (Fig. 1) repre sent in their entirety the duplicate twin shown and which cylinders are preferably made separate and are provided, respectively, with the upper water-jackets 11* and 11", and the lower clearance jackets 12 and 12", which are open at the bottom to the precompression or base chambers 13 and 13 of the power cylinders 10 and 10, which are provided with the base flanges l t and 14* at the bottoms thereof, and the headers 15 and 15 at the tops thereof. Each power cylinder, as 10, is further provided with the inlet and exhaust ports spectively, which communicate with the combustion chamber 18 of the cylinder. Fach cylinder is provided with a port, as 19, which communicates with the valve chamber 20 of the valve casing 21 which is provided with the spring closed automatically operated suction valve 22.

'23 represents the power piston which is preferably of the skirt or barrel type and which is designed as in a two-stroke engine to unport both the inlet and exhaust ports 16 and 17 when in its lower position, as shown in Fig. 2, and to cover and seal said ports when in its upper position, as indicated by the position of the power piston 23 in Fig. 1.

24: represents a stationary seal-plate which is preferably provided with the low pressure stuifing box 25 and the communicating ports 26 and serves as a header for the lower or compression end of the power cylinder 10.

27 represents a common frame housing which is supported and securely coupled with the common bed plate 28 of the'engine, as

shown in Fig. 2; said frame housing 27 being preferably provided across the top thereof with the separate air compartments or reservoirs 29" and 29 which are separated by the common partition wall 30. The common frame housing 27 is preferably pro? vided with the integrally cast crosshead guide bores or crosshead chambers 31 and 31 which are aligned with the power plate 28, as shown in .Fig. 1. 36 and 36 represent the cranks of said crank-shaft !which are used, respectively, with the power cylinders 10 and 10", and are oppositely posltioned at 180 apart, as shown in said Fig.

1. 37 represents a piston type of crosshead which slidably operates within the crosshead guide bore 31" and is coupled with the power piston 23 by the piston rod 38, which 'works 1 through the seal-plate 24, and the crank 36 by the'pitman or connecting rod 39,

as shown in Figs. 1, 2 and 4. 40 represents the oil injection or check valve and 41 repre-- sents the common exhaust pipe of the engine. The power cylinder head 15 may be made integral with the cylinder proper or separate and securely coupled therewith, as indicated in the drawings. The power cylinders are securely bolted to the frame housing 27 with the seal-plates, as 24 (Fig. 2) set between the cylinder and the frame housing. The reservoirs 29 and 29 -serve primarily as conduits to cross-connect the crosshead chambers of one engine unit with the compression or base chamber of the power cylinder of the other en ine unit.

Having thus, describe the parts of my invention in detail, it will be noted that the crosshead bore 31" is open through the ports 32 to the reservoir 29 and that the latter is open through the seal-ports 33" registering with the seal-plate ports 26 to the clearance chamber 12 and the precompression chamber 13. Wherefore, the suction valve 22 of the power cylinder 10 communicates with the crosshead bore 31 of the power cylinder 10*, and further, when the inlet ports 16 are opened by the piston 23 unportin the same the crosshead bore or chamber 31 is putinto direct communication with the combustion chamber 18 of the power cylinder '10.

Similarly the crosshead chamber 31* is cross-connected through the. reservoir 29 with the combustion chamber 18 and communicates therewith through the power. cylinder inlet ports 16. Thus it will be noted that the piston crosshead, as 37%, of one engine unit cooperates with the power piston, as 23", of the other unit, and therefore, because of the opposed crankage therebetween, when-the power piston is traveling upward, its cooperating crosshead piston is traveling simultaneously downward, and vice versa, which accordingly expands or contracts the clearance volumes therebetween. Consequently it will be observed. that each engine First, it will be noted that-the functioning of the parts of the power cylinders 10 and 10 are identical and operate as follows: Assuming that the parts are in the positions shown in Figs. 1 and 2 of-the drawings and that the two power pistons are moving inopposite directions, as indicated .by the arrows (Fig. 1), the piston 23! has just passed its outer dead center position, while the piston 23? has just passed its inner dead center position. a

The working charge, confined within the combustion chamber-of the cylinder 10". is under maximum compression and the fuel oil has just been injected through the spray valve 40 and ignited either by high mechanical compression or by other suitable means such as a spark or hot plate (not shown).

Thus the upward stroke of the power piston, accompanied by the downward stroke of its cross-connected and cooperating crosshead piston, expands the clearance volume ofthe pump unit which supplies the power cylinder of said power piston and sets up a suction against the suction valve of said.

pump unit which automatically opens the valve to atmosphere and the pump unit becomes charged with air; that is, the'suction action set up by the opposed pistons of the pump unit charges the precompresson and clearance chambers of the power cylinder, the crosshead bore, and the reservoir connecting the latter with the precompression and clearance chambers of the power cylin- Also, the downward stroke of the power piston, accompanied by the upward stroke of the cooperating i'ildifiilfik piston of the pump unit, closes the suction valve of the pump unit automatically, contracts the clearance volume of the pump unit, and slightly precompresses the air charged in the 5 pump unit by the previous or suction stroke. Then when the power piston unports, the inlet ports of the power cylinder, which takes place at the lower end of the downward travel of said power piston, the com- 1 bustion chamber of the power cylinder is thus opened into direct'communication with the pump unit associated therewith and the precompressed air therefrom is discharged into said combuston chamber. The employ- 1 ment of the crosshead feature, as herein disclosed, in connection with the pump unit, adds just so much more to the available supply of air to be used in charging and -scavenging the power cylinders of the en.- gine. Ordinarily in the usual two-stroke types of engine the supply percyl nder is limited to the displacement of the power piston, which has been found to be inadequate to provide the full benefits of the F scavenging operation. As must be obviously understood, the within type of pump unit incorporating the crosshead piston displacement, in add tion to the power piston displacement, is thus supplemented with an amount of air equal to the displacement vol ume of' said crosshead piston over-and above the usual power piston displacement; wherefore the said supplemental quantity of air added to the normal quantity of air allowed by the power piston displacement provides an augmented discharge of air with*n the combustion chamber of the power cylinder, which discharge'positively' assures a sulficient air flow to thoroughly scavenge the 'power cylinder and effectively displace the products of. combustion so as to 1nsure a practically unpolluted working charge for the combustion of the injected fuel. This greater cleanliness of the scavenged working charge further results in a more perfeet and rapid combustion, and thus serves to improve the thermal efficiency of the engine.

Naturally the venting of the base chamher (as 13") together with its cross-connected reservoir (as 29) and the crosshead chamber (as 31) will therefore force a charge of air into the combustion chamber (as 18") of the power cylinder (as 10") which is materially larger than could be obtained when working with the power piston displacement alone.

The gain in cylinder power capacity, due to the larger air content retained within the cylinder bore volume lying above the power piston at the instant of exhaust closure, far more than compensates for the relatively small power loss involved in augmenting the air charge by means of the described crosshead piston.

It will thus be noted that the within invention may be readily incorporated into the design of the ordinary types of twin cylinder engines and may be formed within and from the engine parts proper without complicating or disturbing any of the usual characteristics of the engine. The novel pumping feature of the within disclosed invention provides an efiicient and economical scavenging device for internal combustion engines, and yields an increased air content within the confines of the power cylinder as well.

It will thus also be noted from-the above disclosure that the pumping elements required for scavenging the power cylinder are kept extremely simple and that the increased power rating accruing from its use may be absorbed without advancing the first cost per unit of power output It will also be understood that while I describe the suction valves 22 and 22" as being open to atmosphere, the same may be connected differently, as to a source of supply containing air, gas, or mixtures thereof, or other elastic fluid medium according as may be desired.

While the preferred embodiment of my invention has been described in detail, it will be understood that I do not wish to be limited to the particular construction set forth, it being apparent that the described method utilizing the crosshead displacement to supplement the power cylinder air content may readily be applied to both gas and oil engines ofeither the two or four stroke type.

what I claim as new and desire to secure by Letters-Pa-tentis:

1.- In an internal combustion engine having a plurality of power cylinders each having a compression and a crosshead chamber, a pump unit comprising a compression chamber of one power cylinder crossconnected to communicate with a crosshead chamber of another power cylinder, a common suction valve adapted to supply said pump unit with working fluid. and means for discharging the delivery of said pump unit into the respective combustion chamber of the power cylinder for charging and scavenging purposes.

2. In a twin cylinder internal combustion engine having a piston type crosshead provid ed for each cylinder, a pump unit comprising a compression chamber of one of saidtwin cylinders. a crosshead chamber ofthe other of said cylinders, and a conduit means cross Having thus set forth my invention,

Elm

connecting said compression and said crosshead chambers; a fluid supply valve communicating with said conduit; and means for discharging the delivery of said pump unit into the respective combustion chamber of the power cylinder for charging and scav enging purposes.

3. In combination with a twin cylinder internal combustion engine, having opposed cranks and piston type crossheads operating in cylinder guides; means enclosing said cylinder guides to form sealed crosshead chambers; means enclosing the power cylinders of the engine for forming base or compression chambers under the respective power pistons thereof; conduit means for cross-connecting the crosshead chamber of one engine cylinder with the compression chamber of the other engine cylinder; a common suction valve adapted to supply working fluid to said cross-connected cross- I head and compression chambers; and means for discharging and transferring said fluid from said cross-connected crosshead and compression chambers into the combust1on chamber of a power cylinder of the engine 7, for charging and scavenging purposes.

4. An internal combustion engine of the reciprocating type, comprising a set of power cylinders housing oppositely actuated power pistons therein which are each cou-.

pled with a piston type of crosshead operating in cylinders provided therefor; means dividing off the base parts of said power cylinders from the parts of said crosshead cylinders to form compression and crosshead chambers, respectively, for the respective power and crosshead cylinders; means for crossconnecting said crosshead chambers with the compression chambers of the opposite power cylinders for establishing connection therebetween; means for supplying said respective cross-connected chambers with working fluid; and means for discharging said fluid from said cross-connected chambers into the combustion chamber above the respective compression chamber for charging and scavenging said combustion chamber.

5. An internal combustion engine having a pair of power cylinders, each provided with an exhaust, a power piston and a piston rod, a crank mechanism for reciprocating said piston rods in unison, said mechanism comprising a pair of piston crossheads sliding in guide bores provided therefor, means serving to separate each of said guide bores from the bores of said power cylinders to form crosshead and base chambers, respectively, the latter lying'beneath the power pistons and discharging to their respective intake valves, and means establishing communication between the base chamber of one power cylinder and the crosshead chamber of the other power cylinder; said last named crosshead chamber discharging through the intake Valve of the first named power cylinder. v

- 6. In an internal combustion engine a pair of power cylinders, each provided with an intake valve, a power piston and a piston rod, a crank mechanism for reciprocating said piston rods in unison, said mechanism comprising a pair of piston crossheadssliding in guide bores, means serving to separate each of said guide and powercylinder bores into crosshead and base chambers, respectively, conduit means cross-connecting the base chamber of one power cylinder with the crosshead chamber of the other power cylinder, said conduit discharging to the intake port of the first named cylinder, and a common suction valve supplying working fluid to said cross-connected base chamber and crosshead chamber.

formed integral with the frame housing and communicatingwith both the base chamber of. one power cylinder and the crosshead chamber of the second power cylinder, and a suetion valve supplying working fluid to the reservoir and means establishing communication between said reservoir and the intake valve of the first named power cylinder.

8. In an oil'engine of the scavenging type, a pair of power cylinders, each provided with an intake valve, a power piston and a piston rod, a crank mechanism for reciprocating said piston rods in unison, said mechanism comprising a pair of piston crossheads sliding in guide bores, means serving to separate said guide bores from the bores of said power cylinders into crosshead and base chambers, respectively, the latter discharging to their respective power cylinder intake ports, an air supply means for the base chamber of one of the power cylinders, a conduit cross-connecting said base chamber with the crosshead chamber of the second power cylinder, and an air supply means for the last named cylinder crosshead chamber whereby to augment the air discharge from the base chamber of the first named power cylinder.

9. In a reciprocating oil engine of the scavenging type, a pair of power cylinders, each provided with an intake valve, and a power piston, a crank mechanism for reciprocating said pistons in unison, said mechanism comprising a pair of piston cross heads sliding in extend-sail portions of the respective cylinder bores and a pair of piston rods serving to space said crosshead pistons from their respective power pistons, a stationary seal-plate encircling eachvof thepiston rods, a conduit means cross-connecting the chamber formed above said seal-plate in one of the power cylinders with the crosshead chamber formed below said seal-plate of the second power cylinder, and a common suction valve supplying air to said crossconnected chambers.

' 10. In an oil engine of the scavenging type, a pair of power cylinders, each provided with a cylinder bore, a crosshe'ad extension, an intakevalve, a power piston and a piston rod; a crank mechanism for reciprocating said rods in unison and comprising a pair of piston crossheads sliding in said cross-head extensions aligned with their respective cylinder bores; stationary sealplates encircling said rods intermediate their respective power pistons and piston crossheads for providing compression chambers above said piston crossheads in said cylinder etitensions, means for supplying air to the cylinder extension compression chamber of one of the power cylinders, and means for discharging said air into the cylinder bore lying above the power piston of the second power cylinder whereby to augment the air content of the working charge in the last named cylinder. p

11. In an internal combustion engine comprising a power cylinder havlng an intake valve in the sore thereof, a power piston having a barrel portlon adapted to uncover and time said port; a crankshaft mechanism -for actuating said piston, a plurality of charging pump chambers each provided with a separate piston member actuated from said crankshaft and serving as a pumping unit, a conduit cross-connecting said pump chambers, a common suction valve supplying working fluid to said pump chambers, and a discharge means conveying the combined pump delivery to said intake port and into the combustion chamber of the power cylinder for charging and scavenging purposes.

12. In an internal combustion engine comprising a power cylinder having an intake port in the bore thereof, a power piston having a barrel portion adapted to uncover and time said port, a crankshaft mechanism for actuating said piston, a pump unit comprising a base compression chamber and a crosshead chamber each provided with separate piston members actuated from said crankshaft, a conduit cross-connecting said chambers, acommon suction valve supplying working fluid to said pump unit, and a dis charge means conveying the combined pump delivery to said intake port and into the combustion chamber of the power cylinder for charging and scavenging purposes. In testimony whereof, I hereunto aflix my signature, this 13th day of November, 1920.

LOUIS ILLMER. 

